Guest appearances at concerts are great- sometimes it's like getting two concert experiences in one night! Literally the only time I've been disappointed in a surprise guest at a concert was when John Mellencamp stopped the show to bring out presidential candidate John Edwards out to speak (remember him?). I'm not saying it's about politics, though I'm sure roughly half the people at the concert didn't agree with his policies. For me, the guy was just as dry as a popcorn fart and it brought the entire show to a screeching halt. That guest = concert fail.
The opposite of a concert fail? Billy Joel inviting Joe Elliott of Def Leppard onstage in Detroit over the weekend! Check it out:
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